Selective and effective fluorination of organic compounds in water using Selectfluor F-TEDA-BF4

[reaction: see text] Selective and effective fluorination of various types of organic compounds performed in water as the reaction medium using 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (Selectfluor F-TEDA-BF4) is reported. 2-Naphthole and 2-methoxynaphthalene were thus transformed to 1,1-difluoro-2(1H)naphthalenone, estrone to 10beta-fluoro-1,4-estradien-3,17-dione, phenyl-substituted alkenes to vicinal fluorohydrins, and various ketones, 1,3-diketones, or beta-ketoesters to corresponding alpha-fluoro or alpha,alpha-difluoro ketones.